By default, index.yaml not included in the application download. Therefore, if you did not change the skip_files parameter in the skip_files file, you cannot load the index.yaml file.
However, you can customize the files to be included by modifying the skip_files tag in your app.yaml file. Something like that:
skip_files: - ^(.*/)?app\.yaml - ^(.*/)?app\.yml - ^(.*/)?#.*# - ^(.*/)?.*~ - ^(.*/)?.*\.py[co] - ^(.*/)?.*/RCS/.* - ^(.*/)?\..* - ^(.*/)?.*\.bak$
For more information about skip_files, please read: https://developers.google.com/appengine/docs/python/config/appconfig#Skipping_Files
EDIT:
To be more clear. By default, the index.yaml file index.yaml not included in the download. The only way to download the index.yaml file is to first make changes to your app.yaml file, which I suggested. And then download the application again. Unable to upload file that has not been uploaded.
source share